You must have the necessary charts for your flight in the airplane and they must be current. Printing your own, so far as I know, does not satisfy this requirement.If I ask you to take one page that you have printed and demonstrate its valid dates, can you do it.There are now some electronic alternatives but you would have to be careful to be sure that they are certified as equivalent to paper charts for your flight.If you were to be ramp checked or be involved in an incident, you could be violated.

If you are a student pilot, your flight school should be able to direct you to the applicable regulations.If you are a student pilot, your flight school may have something to say about whether they would allow you to use electronic alternatives.Be especially careful to have everything in order on your practical test.

If I ask you to take one page that you have printed and demonstrate its valid dates, can you do it.

Can you do the same with the sectional you went out and bought without unfolding it? After all, that's pretty much the equivalent scenario with a commercial sectional product, right? (I'm assuming "printing your own" means you didn't find a way to print the sectionals on a true single-sheet, sectional-size piece of paper.)

Even if you can't prove the self-printed chart is current... why would that matter? Unless you actually had outdated charts and the use of those charts was determined to have been a contributing factor in an incident, there's no requirement to prove that you have valid/updated charts.